In magnetic resonance imaging (MRI), some measurements of certain types of drilling mud flowing in a conduit or pipe can be lost, particularly as most of the signal that originates at the edges of the pipe corresponds to low velocity and high shear rate. Such signal loss can be evident even in simple spin-echo (SE) images, e.g. images that do not have any intentional velocity-encoding gradients. The degree of signal loss in such measurements can show a positive correlation with echo time and flow rate.
Some methods for measuring a flowing fluid in a conduit to obtain velocity profiles include applying a magnetic pulse to the flowing fluid (e.g., drilling mud) and receiving a response signal. The magnetic pulse applied to the flowing fluid can cause encoding of the velocity information in the response signal (e.g., measurements) in a magnetization direction that is perpendicular to the direction of flow of the fluid within the pipe (e.g., transverse magnetization encoding of velocity information). However, such measurements typically can have signal loss such that the velocity profile may not be accurate. Thus, finding an accurate MRI method for measuring velocity profiles in drilling mud remains a long-felt yet unmet need.